Using P185 tires rather than my stock P195's??

[TripleHelix]

Hi all,

Wondering if doing this is possible?

My old roommate left a couple winter tires when she left and now I'm wondering if I can put these on my car or not.

I believe they were from a MAzda 3 and I drive a 97 cavalier.

The rest of the stats match (P195 70R14 vs P185 70R14)

Will they fit on my rims? (steel rims)

Thanks

[thumper80]

I would use them if the treads better than you have on now , the only difference is 10 millimeters of tread width . And yes they will fit on your current rims.

[TripleHelix]

I would use them if the treads better than you have on now , the only difference is 10 millimeters of tread width . And yes they will fit on your current rims.

These being smaller in diamater will cause my odo and speedo to be off by a bit right?

This would mean my speedo showing me going faster than what I'm actually doing right (I know it wont be by much...)

[thumper80]

These being smaller in diamater will cause my odo and speedo to be off by a bit right?

This would mean my speedo showing me going faster than what I'm actually doing right (I know it wont be by much...)

It won't affect it at all , if you were changing the height of the tire it would like from 195/70/r14 to a 195/75/r15 it would .

[TripleHelix]

Tire 1 - 185/70R14
Tire 2 - 195/70R14

Section Width: 7.28 in 185 mm
Section Width: 7.67 in 195 mm

Rim Diameter: 14 in 355.6 mm
Rim Diameter: 14 in 355.6 mm

Rim Width Range: 5 - 6.5 in
Rim Width Range: 5.5 - 7 in

Overall Diameter: 24.19 in 614.42 mm
Overall Diameter: 24.74 in 628.39 mm

Sidewall Height: 5.09 in 129.28 mm
Sidewall Height: 5.37 in 136.39 mm

Radius: 12.09 in 307.08 mm
Radius: 12.37 in 314.19 mm

Circumference: 75.99 in 1930.1 mm
Circumference: 77.72 in 1974.0 mm

Revs per Mile: 859.8
Revs per Mile: 840.7

It does affect it...

[thumper80]

Tire 1 - 185/70R14
Tire 2 - 195/70R14

Section Width: 7.28 in 185 mm
Section Width: 7.67 in 195 mm

Rim Diameter: 14 in 355.6 mm
Rim Diameter: 14 in 355.6 mm

Rim Width Range: 5 - 6.5 in
Rim Width Range: 5.5 - 7 in

Overall Diameter: 24.19 in 614.42 mm
Overall Diameter: 24.74 in 628.39 mm

Sidewall Height: 5.09 in 129.28 mm
Sidewall Height: 5.37 in 136.39 mm

Radius: 12.09 in 307.08 mm
Radius: 12.37 in 314.19 mm

Circumference: 75.99 in 1930.1 mm
Circumference: 77.72 in 1974.0 mm

Revs per Mile: 859.8
Revs per Mile: 840.7

It does affect it...

width of the tire doesn't affect the speedo , it's the over height of the tire that affects the speedo calibration .

[banban]

Go for it
it won't make a huge difference in speed or quality of ride

most people go with smaller tires in the winter and wider tires in the summer

[D-3vil]

width of the tire doesn't affect the speedo , it's the over height of the tire that affects the speedo calibration .

thumper, please make sure you understand what the tire dimensions actually refer to. The height of the tire is always indicated as a percentage of the width.

so, for 195/70R14: height = 70% of 195mm
for 185/70R14: height = 70% of 185 mm.

That gives you a radius differential of 7.0mm, which is quite a lot.

If OP chooses a narrower tire, s/he should increase the aspect ratio. Going form 195/70R14 to 185/75R14 results in a negligible change in overall diameter.

To answer the OP's question correctly, I would recommend against using these tires -- not as much because of the size difference, but because you won't gain any advantages from doing so. If you do choose to mount them, they'd have to be mounted on the back (otherwise you're at high risk of fishtailing when braking on a slipper surface).


Go for it
it won't make a huge difference in speed or quality of ride

most people go with smaller tires in the winter and wider tires in the summer
Most people opt for narrower tires in the winter, not smaller ones (and they definitely don't opt for different tire sizes front/back). Overall tire diameter should remain the same.

[googoo]

width of the tire doesn't affect the speedo , it's the over height of the tire that affects the speedo calibration .

Wow, missing something there aren't we?

the "70" in the 195/70 14" is the percentage of the height to the width of the tire, SSooooo 70% of 195mm is more than 70% of 185mm, grab your calculator and try it, it works:lol:

Brent

[TripleHelix]

thumper, please make sure you understand what the tire dimensions actually refer to. The height of the tire is always indicated as a percentage of the width.

so, for 195/70R14: height = 70% of 195mm
for 185/70R14: height = 70% of 185 mm.

That gives you a radius differential of 7.0mm, which is quite a lot.

If OP chooses a narrower tire, s/he should increase the aspect ratio. Going form 195/70R14 to 185/75R14 results in a negligible change in overall diameter.

To answer the OP's question correctly, I would recommend against using these tires -- not as much because of the size difference, but because you won't gain any advantages from doing so. If you do choose to mount them, they'd have to be mounted on the back (otherwise you're at high risk of fishtailing when braking on a slipper surface).


Most people opt for narrower tires in the winter, not smaller ones (and they definitely don't opt for different tire sizes front/back). Overall tire diameter should remain the same.

All this has to do with me using tires I already have (Free) vs buying new ones. The car won't last me much longer (probably buying something else next summer or so), so this is only to keep me going until then.

This is a 97 Cavalier after all and wont be much more then scrap money once I do decide to get rid of it (which like I said is 1-1.5 years max).

And why would you put the smaller tires in the back?

I have 195s on my car currently...

The other thing is 7mm could easily (ok maybe not easily) be the difference in wear if replacing the tires at different times right? So is it really that big of an issue?

I haven't once replaced all 4 tires at once so I could easily of had that much difference in tread...

[TripleHelix]

width of the tire doesn't affect the speedo , it's the over height of the tire that affects the speedo calibration .

As you can see in the comparison, diameter and Rotations per mile are different between the two, so it does make a difference...

[CUVShopper]

use this to compare:

http://www.miata.net/garage/tirecalc.html

the 185's will make your speedo 2.2% faster. 3% or less difference is considered safe.

[TripleHelix]

use this to compare:

http://www.miata.net/garage/tirecalc.html

the 185's will make your speedo 2.2% faster. 3% or less difference is considered safe.

Safe for speed difference but is it safe to have different tires in front/back...

[MS MSP]

width of the tire doesn't affect the speedo , it's the over height of the tire that affects the speedo calibration .

someone ban this guy for posting BS.

The middle number/aspect ratio (70 in this case) is percentage of width, not a fixed number.

Meaning it does affect the speedo calibration.

[fastlayne]

It won't affect it at all , if you were changing the height of the tire it would like from 195/70/r14 to a 195/75/r15 it would .


width of the tire doesn't affect the speedo , it's the over height of the tire that affects the speedo calibration .

Tire 101 = Fail.

As others have pointed out the sidewall heights, 185*.70 versus 195*.70 are not the same.

[fastlayne]

use this to compare:

http://www.miata.net/garage/tirecalc.html

the 185's will make your speedo 2.2% faster. 3% or less difference is considered safe.

And just to clarify for the OP. When the speedometer indicates 100km/h, the car is actually doing a little less than 98.

And when you are stunt driving at an indicated 150, you are only doing 147 - so you have a safety margin. ;)

[robz]

go for it!

smaller and narrower tires are way better for winter... these tires of yours are narrower so do it...

robz

[TripleHelix]

Even if I will be just replacing 2/4 tires and keeping the wider ones in the back?

[D-3vil]

Even if I will be just replacing 2/4 tires and keeping the wider ones in the back?

Like I stated previously, if you do opt to use these tires, they should go on the back.

The reason for this is, these new winter tires not only will have better grip because of the softer rubber compound, they will also be thinner, meaning they will cut through the slush and snow better. These two factors alone mean this pair of tires will grip much better than your other one, especially in slippery conditions.

Now that that's been established, look at the dis/advantages of mounting the new tires on the back:
- same traction as before when accelerating (as your car is FWD)
- slightly better braking due to the increased grip (as only about 20-30% of the braking is done by your rear wheels). Your front tires will lose grip before your rears, which will still have you braking in a straight line until you stop.

Doesn't look like much, does it? But consider the dis/advantages of mounting them on the front:
- better traction when accelerating, however
- high probability of losing control and fishtailing when braking on a slippery surface: your rear tires will lose grip before your fronts, causing your rear to slide and your car to fishtail. THIS IS EXTREMELY HAZARDOUS!

We're now back to my original statement: you should mount the smaller, thinner tires on the back. Yes, your car will look weird, but let's face it, it's a '97 Cavalier which you're not planning to keep for long -- so this is the price you'd be paying for your otherwise free tires. You can find some consolation in the fact that the new tires aren't that much smaller compared to the old ones, so it will be hard to notice.

To put things in perspective further: if you read all this, and you still opt to mount the winter tires on the front, I sincerely hope you'll get lucky and have an event-free winter. But if something were to happen, I REALLY hope you don't injure anyone else -- though by that time things will be entirely out of your control.

[banban]

thumper, please make sure you understand
Most people opt for narrower tires in the winter, not smaller ones (and they definitely don't opt for different tire sizes front/back). Overall tire diameter should remain the same.

sorry I meant narrower tires not smaller

[jeev155]

they will make your car explode